Question

please answer this question ​

Answer 1

Answer:

$\huge\boxed{1}\\\boxed{x=5}$

Step-by-step explanation:

$\left(5^{-2}\div5^{-8}\right)\times5^{-6}\\\\\text{use}\ a^n\div a^m=a^{n-m}\ \text{and}\ a^n\times a^m=a^{n+m}\\\\=5^{-2-(-8)+(-6)}=5^{-2+8-6}=5^0=1$

$3^x=243\\\\3^x=3^5\Rightarrow x=5$